Effect of oxidant sources on carbon-related impurities in ALD-Al2O3 for solid-state devices

Abstract

In this study, we investigated the effect of oxidant sources on carbon-related impurities in atomic layer deposited (ALD)-Al2O3 by focusing on the plasma-induced decomposition of –CH3 groups which is attributed to ALD precursor. We found that C–O bonds were detected in ALD-Al2O3 using O2 plasma instead of the C–H bonds which is attributed to the –CH3 groups of trimethylaluminum. It is considered that the decomposition of –CH3 groups was enhanced by O2 plasma, and C–O residue was generated. We concluded that the decomposition of –CH3 groups by oxidant sources must be suppressed to reduce the carbon-related impurities in ALD-Al2O3.